brown algae

[Reefer769]

this is probably a stupid question, but why is it that when my 150w hqi mh 20k light turns on in the morning the sandbed and rock look beautiful clear of any algae at all, but when a couple of hours pass with the light on this brown film/hairy algae forms on the sandbed and parts of the rock. so its like this algae appears and disappears on a daily basis, whats going on here?

[Reefland]

Hey Reefer. Diatoms...

[Ninong]

whats going on here?

Photosynthesis. Followed by reproduction via cell division. They're unicellular. Their cell walls are made of silica. They have yellowish-brown chloroplasts that they use in photosynthesis.

No silicate = no diatoms. Once they exhaust the available silicate, they will die down. Unless, of course, you're adding silicate one way or another.

[Reefer769]

nice
now in what ways could i be adding silicate?

[Ninong]

Some people use unfiltered tapwater or well water to make their saltwater and sometimes their freshwater contains silicates.

[Reefer769]

i dont use tapwater though, i just buy distilled water by the gallon

[Ninong]

i dont use tapwater though, i just buy distilled water by the gallon

Good.

[Ninong]

A diatom bloom is common during the early stages (first few weeks) of cycling a new aquarium. It usually last no longer than 10 days to two weeks, after which it just fades away on its own.

Once an aquarium has been established for some time, it's still possible for diatoms to become an obvious nuisance. The question is not whether you have any diatoms at all in your tank, it's whether they are obvious or not. In a sense, you might compare them to cyanobacteria in that neither is a problem unless they become obvious and start covering up everything.

The only point I was trying to make about silicate is that since the diatoms require silica to construct their cell walls, silica is a limiting factor.

[Reefer769]

i think i just need to do a little cleaning inside the tank maybe pick up a few more turbos to get rid of some detris. its to bad that i cant find my protein skimmer that probably would have come in handy.

[cdearing]

Hi Reefer,

Did you ever get rid of your algae? What did you find did the trick? My tank is a year old and for about the last month, I have been having this problem, more like red algae that bubbles stick to on the rock and sand bed. I have added one turbo in my 30 gallon. I have a good skimmer. I do weekly water changes and have recently started rinsing the frozen food and straining it before putting in the tank. I'm afraid that I might be underfeeding to compensate for this obnoxious problem.

Cynthia